The trailer transportation of heavy farm and industrial equipment requires special loading ramps at the rear end of the trailer. FIG. 1 of the patent drawings illustrates a typical prior art trailer wherein a hinged ramp is raised and lowered by a hydraulic cylinder or the like. The ramp of the prior art as illustrated in FIG. 1 has been generally satisfactory but it does have some serious disadvantages and/or limitations. In the prior art trailer, a significant amount of the trailer deck is unusable for carrying cargo. The ramp tail of the prior art trailer also causes a load imbalance at the rear of the trailer suspension centerline. Additionally, the prior art trailer requires that the axle must be located forwardly of the ramp hinge which causes a reduction of the payload due to increased suspension loading. Further, lower legal axle loading is necessary in the prior art trailers due to bridge laws which normally specify the ground load limits for groups of axles located at given spaced distances. As the distance between succeeding axles increases, ground allowable loads also increase.
It is therefore a principal object of the invention to provide a trailer including a multiple fold ramp tail wherein an increased amount of trailer deck is usable for carrying cargo.
A further object of the invention is to provide a trailer of the type described wherein a load imbalance at the rear of the trailer suspension centerline is avoided.
A still further object of the invention is to provide a trailer of the type described wherein the hinge between the main frame and the ramp is positioned directly above the rearward most axle centerline.
A further object of the invention is to provide a trailer of the type described including a simplified lock mechanism which maintains the ramp in the operative cargo carrying position.
A still further object of the invention is to provide a trailer of the type described which is durable and convenient.
These and other objects will be apparent to those skilled in the art.